The 27-year-old Russian is having quite a comeback from six months off with a knee injury,having arrived at the Australian Open ranked No. 75 and unseeded at a Slam for the first time since 2003. Kuznetsova, the winner of the 2004 US Open and 2009 Roland Garros, defeated Wozniacki 62 26 75 to set up her clash with the world No. 1.

“It's amazing. It's my best result. I have been two times to quarterfinals (here previously), so I'm just kind of replaying that. It's very good result for first tournament, for first Grand Slam (back), and especially I don't remember when I was in quarters.”

Her last visit to the final eight of a major was in fact at Roland Garros in 2011. Kutnetsova didn’t play again after Wimbledon last year, but since her comeback has compiled a 6-2 record. She had already defeated Wozniacki once this year, on her way to reaching the quarterfinals at Sydney two weeks ago, and the Dane was her second seeded victim at the Australian Open after her defeat of No. 26 seed Su-Wei Hsieh in the second round.

Kuznetsova says her time out on crutches has given her a new appreciation for her sport, and that the break has done her good. She had considered having a rest anyway, but “I maybe wouldn't have balls to take it, you know, because it's quite a big decision to do that. Because you never know how you're going to recover, if you're going to lose matches, if you not. Here I think it was time to just stop. My body was not able to hold anymore, and mentally I was not there, as well.”

Recuperating in Russia among family and friends, “I had time home and just refresh my mind, and then I just understood that I want to play this game.”

Her biggest test is sure to come when she faces Azarenka on Tuesday in a battle of two Grand Slam champions. Kuznetsova has a 4-3 record against the Belarusian, but she hasn’t won since 2009. Since then Azarenka has beaten her twice in straight sets. ”She's tough; she's No. 1; I have nothing to lose; she has all the pressure. I know I got the game to give her some problems, and I will just do my best and just try to enjoy it.”

Two other Russians weren’t so lucky on Monday. Azarenka’s safe passage to the last eight came at the expense of Elena Vesnina, whom she defeated 61 61 in 57 minutes. Under the lights of Rod Laver Arena, Serena Williams barely broke sweat in her 62 60 win against Maria Kirilenko, also achieved in 57 minutes. The American, who has lost just eight games in Melbourne so far, faces her teenage compatriot Sloane Stephens next. The No. 29 seed, who had posters of Serena and sister Venus on her walls growing up, is through to her first Grand Slam quarterfinal after defeating Bojana Jovanovski 61 36 75.

Jeremy Chardy is turning into the surprise package of the men’s tournament as he beat his third seeded opponent in a row on Monday to book a place in his first Grand Slam quarterfinal. The Frenchman was Saturday’s giant-killer, ousting No. 6 seed Juan Martin del Potro in five sets, and he followed it up with a four-set victory over No. 21 seed Andreas Seppi 57 63 62 62.

“I know I can beat everybody,” said the 25-year-old Chardy. “So when I feel confident, I believe in me. Against del Potro, I play a very good match. So it was good for my head. And today it was difficult after my win yesterday. I think when I lose the first set 75, I forget it. I say, Okay, now I have to play, because I was a little bit nervous. After I play more I relax.”

Chardy meets No. 3 seed Andy Murray in the last eight after the US Open champion had a routine win over an exhausted Gilles Simon 63 61 63. Murray has a 4-1 record against Chardy, although the Frenchman did upset him in Cincinnati last summer.

Wilfried Tsonga won an all-French battle against Davis Cup teammate Richard Gasquet 64 36 63 62 to make it two Frenchmen in the quarterfinals. The 2008 Australian Open runner-up will play Roger Federer next in what will be their 12th match-up, with the Swiss leading the series 8-3. Federer sealed his place in the next round with a 64 76(4) 62 victory against No. 13 seed Milos Raonic in a Rod Laver Arena night match which promised more than it could ultimately deliver, at least for the rising Canadian.